drivers/clk/clk-s2mps11.c

   1 /*
   2  * clk-s2mps11.c - Clock driver for S2MPS11.
   3  *
   4  * Copyright (C) 2013,2014 Samsung Electornics
   5  *
   6  * This program is free software; you can redistribute  it and/or modify it
   7  * under  the terms of  the GNU General  Public License as published by the
   8  * Free Software Foundation;  either version 2 of the  License, or (at your
   9  * option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  */
  17
  18 #include <linux/module.h>
  19 #include <linux/err.h>
  20 #include <linux/of.h>
  21 #include <linux/clkdev.h>
  22 #include <linux/regmap.h>
  23 #include <linux/clk-provider.h>
  24 #include <linux/platform_device.h>
  25 #include <linux/mfd/samsung/s2mps11.h>
  26 #include <linux/mfd/samsung/s2mps13.h>
  27 #include <linux/mfd/samsung/s2mps14.h>
  28 #include <linux/mfd/samsung/s5m8767.h>
  29 #include <linux/mfd/samsung/core.h>
  30
  31 enum {
  32         S2MPS11_CLK_AP = 0,
  33         S2MPS11_CLK_CP,
  34         S2MPS11_CLK_BT,
  35         S2MPS11_CLKS_NUM,
  36 };
  37
  38 struct s2mps11_clk {
  39         struct sec_pmic_dev *iodev;
  40         struct device_node *clk_np;
  41         struct clk_hw hw;
  42         struct clk *clk;
  43         struct clk_lookup *lookup;
  44         u32 mask;
  45         unsigned int reg;
  46 };
  47
  48 static struct s2mps11_clk *to_s2mps11_clk(struct clk_hw *hw)
  49 {
  50         return container_of(hw, struct s2mps11_clk, hw);
  51 }
  52
  53 static int s2mps11_clk_prepare(struct clk_hw *hw)
  54 {
  55         struct s2mps11_clk *s2mps11 = to_s2mps11_clk(hw);
  56
  57         return regmap_update_bits(s2mps11->iodev->regmap_pmic,
  58                                  s2mps11->reg,
  59                                  s2mps11->mask, s2mps11->mask);
  60 }
  61
  62 static void s2mps11_clk_unprepare(struct clk_hw *hw)
  63 {
  64         struct s2mps11_clk *s2mps11 = to_s2mps11_clk(hw);
  65
  66         regmap_update_bits(s2mps11->iodev->regmap_pmic, s2mps11->reg,
  67                            s2mps11->mask, ~s2mps11->mask);
  68 }
  69
  70 static int s2mps11_clk_is_prepared(struct clk_hw *hw)
  71 {
  72         int ret;
  73         u32 val;
  74         struct s2mps11_clk *s2mps11 = to_s2mps11_clk(hw);
  75
  76         ret = regmap_read(s2mps11->iodev->regmap_pmic,
  77                                 s2mps11->reg, &val);
  78         if (ret < 0)
  79                 return -EINVAL;
  80
  81         return val & s2mps11->mask;
  82 }
  83
  84 static unsigned long s2mps11_clk_recalc_rate(struct clk_hw *hw,
  85                                              unsigned long parent_rate)
  86 {
  87         return 32768;
  88 }
  89
  90 static struct clk_ops s2mps11_clk_ops = {
  91         .prepare        = s2mps11_clk_prepare,
  92         .unprepare      = s2mps11_clk_unprepare,
  93         .is_prepared    = s2mps11_clk_is_prepared,
  94         .recalc_rate    = s2mps11_clk_recalc_rate,
  95 };
  96
  97 /* This s2mps11_clks_init tructure is common to s2mps11, s2mps13 and s2mps14 */
  98 static struct clk_init_data s2mps11_clks_init[S2MPS11_CLKS_NUM] = {
  99         [S2MPS11_CLK_AP] = {
 100                 .name = "s2mps11_ap",
 101                 .ops = &s2mps11_clk_ops,
 102         },
 103         [S2MPS11_CLK_CP] = {
 104                 .name = "s2mps11_cp",
 105                 .ops = &s2mps11_clk_ops,
 106         },
 107         [S2MPS11_CLK_BT] = {
 108                 .name = "s2mps11_bt",
 109                 .ops = &s2mps11_clk_ops,
 110         },
 111 };
 112
 113 static struct device_node *s2mps11_clk_parse_dt(struct platform_device *pdev,
 114                 struct clk_init_data *clks_init)
 115 {
 116         struct sec_pmic_dev *iodev = dev_get_drvdata(pdev->dev.parent);
 117         struct device_node *clk_np;
 118         int i;
 119
 120         if (!iodev->dev->of_node)
 121                 return ERR_PTR(-EINVAL);
 122
 123         clk_np = of_get_child_by_name(iodev->dev->of_node, "clocks");
 124         if (!clk_np) {
 125                 dev_err(&pdev->dev, "could not find clock sub-node\n");
 126                 return ERR_PTR(-EINVAL);
 127         }
 128
 129         for (i = 0; i < S2MPS11_CLKS_NUM; i++)
 130                 of_property_read_string_index(clk_np, "clock-output-names", i,
 131                                 &clks_init[i].name);
 132
 133         return clk_np;
 134 }
 135
 136 static int s2mps11_clk_probe(struct platform_device *pdev)
 137 {
 138         struct sec_pmic_dev *iodev = dev_get_drvdata(pdev->dev.parent);
 139         struct s2mps11_clk *s2mps11_clks;
 140         struct clk_hw_onecell_data *clk_data;
 141         unsigned int s2mps11_reg;
 142         int i, ret = 0;
 143         enum sec_device_type hwid = platform_get_device_id(pdev)->driver_data;
 144
 145         s2mps11_clks = devm_kcalloc(&pdev->dev, S2MPS11_CLKS_NUM,
 146                                 sizeof(*s2mps11_clks), GFP_KERNEL);
 147         if (!s2mps11_clks)
 148                 return -ENOMEM;
 149
 150         clk_data = devm_kzalloc(&pdev->dev,
 151                                 struct_size(clk_data, hws, S2MPS11_CLKS_NUM),
 152                                 GFP_KERNEL);
 153         if (!clk_data)
 154                 return -ENOMEM;
 155
 156         switch (hwid) {
 157         case S2MPS11X:
 158                 s2mps11_reg = S2MPS11_REG_RTC_CTRL;
 159                 break;
 160         case S2MPS13X:
 161                 s2mps11_reg = S2MPS13_REG_RTCCTRL;
 162                 break;
 163         case S2MPS14X:
 164                 s2mps11_reg = S2MPS14_REG_RTCCTRL;
 165                 break;
 166         case S5M8767X:
 167                 s2mps11_reg = S5M8767_REG_CTRL1;
 168                 break;
 169         default:
 170                 dev_err(&pdev->dev, "Invalid device type\n");
 171                 return -EINVAL;
 172         }
 173
 174         /* Store clocks of_node in first element of s2mps11_clks array */
 175         s2mps11_clks->clk_np = s2mps11_clk_parse_dt(pdev, s2mps11_clks_init);
 176         if (IS_ERR(s2mps11_clks->clk_np))
 177                 return PTR_ERR(s2mps11_clks->clk_np);
 178
 179         for (i = 0; i < S2MPS11_CLKS_NUM; i++) {
 180                 if (i == S2MPS11_CLK_CP && hwid == S2MPS14X)
 181                         continue; /* Skip clocks not present in some devices */
 182                 s2mps11_clks[i].iodev = iodev;
 183                 s2mps11_clks[i].hw.init = &s2mps11_clks_init[i];
 184                 s2mps11_clks[i].mask = 1 << i;
 185                 s2mps11_clks[i].reg = s2mps11_reg;
 186
 187                 s2mps11_clks[i].clk = devm_clk_register(&pdev->dev,
 188                                                         &s2mps11_clks[i].hw);
 189                 if (IS_ERR(s2mps11_clks[i].clk)) {
 190                         dev_err(&pdev->dev, "Fail to register : %s\n",
 191                                                 s2mps11_clks_init[i].name);
 192                         ret = PTR_ERR(s2mps11_clks[i].clk);
 193                         goto err_reg;
 194                 }
 195
 196                 s2mps11_clks[i].lookup = clkdev_hw_create(&s2mps11_clks[i].hw,
 197                                         s2mps11_clks_init[i].name, NULL);
 198                 if (!s2mps11_clks[i].lookup) {
 199                         ret = -ENOMEM;
 200                         goto err_reg;
 201                 }
 202                 clk_data->hws[i] = &s2mps11_clks[i].hw;
 203         }
 204
 205         clk_data->num = S2MPS11_CLKS_NUM;
 206         of_clk_add_hw_provider(s2mps11_clks->clk_np, of_clk_hw_onecell_get,
 207                                clk_data);
 208
 209         platform_set_drvdata(pdev, s2mps11_clks);
 210
 211         return ret;
 212
 213 err_reg:
 214         while (--i >= 0)
 215                 clkdev_drop(s2mps11_clks[i].lookup);
 216
 217         return ret;
 218 }
 219
 220 static int s2mps11_clk_remove(struct platform_device *pdev)
 221 {
 222         struct s2mps11_clk *s2mps11_clks = platform_get_drvdata(pdev);
 223         int i;
 224
 225         of_clk_del_provider(s2mps11_clks[0].clk_np);
 226         /* Drop the reference obtained in s2mps11_clk_parse_dt */
 227         of_node_put(s2mps11_clks[0].clk_np);
 228
 229         for (i = 0; i < S2MPS11_CLKS_NUM; i++) {
 230                 /* Skip clocks not present on S2MPS14 */
 231                 if (!s2mps11_clks[i].lookup)
 232                         continue;
 233                 clkdev_drop(s2mps11_clks[i].lookup);
 234         }
 235
 236         return 0;
 237 }
 238
 239 static const struct platform_device_id s2mps11_clk_id[] = {
 240         { "s2mps11-clk", S2MPS11X},
 241         { "s2mps13-clk", S2MPS13X},
 242         { "s2mps14-clk", S2MPS14X},
 243         { "s5m8767-clk", S5M8767X},
 244         { },
 245 };
 246 MODULE_DEVICE_TABLE(platform, s2mps11_clk_id);
 247
 248 #ifdef CONFIG_OF
 249 /*
 250  * Device is instantiated through parent MFD device and device matching is done
 251  * through platform_device_id.
 252  *
 253  * However if device's DT node contains proper clock compatible and driver is
 254  * built as a module, then the *module* matching will be done trough DT aliases.
 255  * This requires of_device_id table.  In the same time this will not change the
 256  * actual *device* matching so do not add .of_match_table.
 257  */
 258 static const struct of_device_id s2mps11_dt_match[] = {
 259         {
 260                 .compatible = "samsung,s2mps11-clk",
 261                 .data = (void *)S2MPS11X,
 262         }, {
 263                 .compatible = "samsung,s2mps13-clk",
 264                 .data = (void *)S2MPS13X,
 265         }, {
 266                 .compatible = "samsung,s2mps14-clk",
 267                 .data = (void *)S2MPS14X,
 268         }, {
 269                 .compatible = "samsung,s5m8767-clk",
 270                 .data = (void *)S5M8767X,
 271         }, {
 272                 /* Sentinel */
 273         },
 274 };
 275 MODULE_DEVICE_TABLE(of, s2mps11_dt_match);
 276 #endif
 277
 278 static struct platform_driver s2mps11_clk_driver = {
 279         .driver = {
 280                 .name  = "s2mps11-clk",
 281         },
 282         .probe = s2mps11_clk_probe,
 283         .remove = s2mps11_clk_remove,
 284         .id_table = s2mps11_clk_id,
 285 };
 286
 287 static int __init s2mps11_clk_init(void)
 288 {
 289         return platform_driver_register(&s2mps11_clk_driver);
 290 }
 291 subsys_initcall(s2mps11_clk_init);
 292
 293 static void __exit s2mps11_clk_cleanup(void)
 294 {
 295         platform_driver_unregister(&s2mps11_clk_driver);
 296 }
 297 module_exit(s2mps11_clk_cleanup);
 298
 299 MODULE_DESCRIPTION("S2MPS11 Clock Driver");
 300 MODULE_AUTHOR("Yadwinder Singh Brar <yadi.brar@samsung.com>");
 301 MODULE_LICENSE("GPL");